The exterior surfaces of houses and other structures are often protected by exterior siding products made from wood, vinyl, aluminum, bricks, stucco, fiber-cement and other materials. Wood and fiber-cement siding (FCS) products, for example, are generally planks, panels or shakes that are “hung” on plywood or composite walls. Although wood siding products are popular, wood siding can become unsightly or even defective because it may rot, warp or crack. Additionally, wood siding products are also highly flammable and subject to insect damage. FCS is an excellent building material because it is nonflammable, weatherproof, and relatively inexpensive to manufacture. Moreover, FCS does not rot and insects do not consume the fiber-cement composites.
FIG. 1 shows a prior art fiber-cement shake panel 20 having a length L extending along a longitudinal dimension, and a width extending along a transverse dimension that varies along the length L from a width W1 to a width W2. The shake panel 20 has side edges 23 separated from each other by the length L, a top edge 22 extending along the longitudinal dimension between the upper ends of the side edges 23, and a bottom edge 24 extending along the longitudinal dimension between the bottom ends of the side edges 23. The top and bottom edges 22 and 24 are typically substantially parallel to each other and separated by a widthwise dimension (W1 and W2) of the shake panel 20. The shake panel 20 also includes a web portion 32 and a plurality of shake sections 30a and 30b of different lengths LS1, and LS2 projecting from the web portion 32 and separated by slots 28. The shake sections 30a and 30b, accordingly, have widths WS corresponding to the distance between slots 28. It is particularly important that the lower edge 24 be a rough, cut edge to give the appearance that the fiber-cement shake panel 20 is formed of wood and cut with a saw.
A prior art cutting machine 34 suitable for forming the shake panel 20 is shown in FIG. 2. The cutting machine 34 includes a frame 36, a plurality of cutting stations 35a-35d, and a plurality of rollers 58 for supporting and advancing a sheet of fiber-cement to be cut. The first cutting station 35a includes a plurality of actuators 38 attached to the frame 36 and a driver 40 projecting from each of the actuators 38. The first cutting station 35a further includes a platform 44 slidably attached to the frame 36 and a fixed platform 52 attached to the frame 36. The actuators 38 are operable to extend and retract the drivers 40 in order to move the platform 44 upwardly and downwardly in the direction A. The first cutting station 35a also includes a upper blade assembly 42 and a lower blade assembly 50. The upper blade assembly 42 includes a first blade holder 46 attached to the movable platform 44 and a first blade 48 attached to the first blade holder 46. The lower blade assembly 50 includes a second blade holder 54 attached to the fixed platform 52. A second blade 56 is attached to the second blade holder 54. The first and second blades 48 and 56 are aligned with each other and, respectively, extend along a length sufficient to singulate a plank from the larger sheet of fiber-cement. The first cutting station 35a is used to cut a plurality of planks from a larger sheet of fiber-cement and will be discussed in more detail below.
The second cutting station 35b includes a slot cutting assembly 53 including a blade holder 54 having a plurality of slot cutting blades 56 attached thereto. Each of the slot cutting blades 56 is configured to cut the slots 28 shown in the shake panel 20 of FIG. 1. The blade holder 54 is pivotally connected to the frame 36 and may be rotated between a cutting position and a retracted position in the direction R by extension and retraction of an actuator 58 coupled to the blade holder 54.
The third cutting station 35c includes a cutting assembly 63 very similar to the cutting assembly 53 of the second cutting station 35b. The third cutting station 35c also includes a blade holder 62 pivotally connected to the frame 36 and operable to be rotated in the direction R, as shown, by extension and retraction of an actuator 60 coupled to the blade holder 62. A plurality of slot cutting blades 64 are attached to the blade holder 62 and each of the slot cutting blades 64 are configured to cut the slots 28 shown in the shake panel 20 of FIG. 1. However, as will be discussed in more detail below, in operation, the cutting assembly 63 is used to cut the slots 28 in every plank cut from the sheet of fiber-cement except for the slots 28 cut in the last plank, which are cut by the second cutting assembly 35b. 
The fourth cutting station 35d is a configured to cut the shake sections 30a of the shake panel 20 in order to vary the lengths (LS1, and LS2) of the shake sections as shown in FIG. 1. The cutting assembly 65 includes a plurality of actuators 74 attached to the frame 34 and a driver 76 projecting from each of the actuators 74. The fourth cutting station 35d further includes a movable platform 66 slidably attached to the frame 36 and a fixed platform 72 attached to the frame 36. The actuators 76 are operable to extend and retract the drivers 76 in order to move the platform 66 upwardly and downwardly in the direction A. The fourth cutting station 35d also includes a plurality of first blade assemblies 65 and second blade assemblies 75. Each of the first blade assemblies 65 includes a first blade holder 68 attached to the movable platform 66 and first blade 70 attached to the first blade holder 68. Each of the second blade assemblies 75 includes a second blade holder 74 attached to the fixed platform 72 and a second blade 76 is attached to the second blade holder 74. The first and second blade assemblies 65 and 75 are staggered and arranged in transversely spaced apart pairs with their respective first and second blades 70 and 76 aligned with each other. Accordingly, the fourth cutting station 35d may cut the shake sections 30a of the shake panel 20 to vary the length.
With reference to FIGS. 2 and 3, in operation, a fiber-cement sheet 80 is provided and advanced along a path P1 to the first cutting station 35a. The sheet 80 includes first and second edges 82 and 84 each having a length equal to L, and side edges 86, all of which are very smooth because they were cut using a process such as water jet cutting. The sheet 80 may be cut into a plurality of planks 90a-90e. Although five planks 90-90e are shown in FIG. 3, the sheet 80 may be cut into a different number of planks depending on the size of the sheet 80 and the planks to be cut therefrom. At the first cutting station 35a, the sheet 80 is cut into a first plank 90a along a cutting plane C1 and is advanced to the third cutting station 35c. At the third cutting station 35c, the slots 28 are formed in the first plank 90a and the shake panel 20a is formed. Simultaneously, with advancing the first plank 90a to the third cutting station 35c, the sheet 80 is advanced along the path P1 to align cutting plane C2 thereof with the first and second blades 48 and 54 of the first cutting station 35a. A second plank 90b is cut from the sheet 80 along a cutting plane C2 using the first cutting station 35a. The second plank 90b is advanced along the path P1 to the third cutting station 35c where the slots 28 are cut in second plank 90b to form the shake panel 20b and the shake sections 30a thereof. If desired, as the slots 28 are being formed in the plank 90b, the shake panel 20a may be advanced in the direction P1to the fourth cutting station 35d where the length of the shake sections 30a thereof may be trimmed.
This process is continuously repeated until the fifth/last plank 90e is ready to have the slots 28 formed therein. The upstream edge 84 of the fifth plank 90e has a factory edge that was cut using a technique such as water jet cutting, which produces a very smooth edge. However, consumers would like the edge 24 of the shake panel 20e to have a rough cut edge giving the appearance of a wood product cut with a saw. Thus, the fifth plank 90e is advanced to the second cutting station 35b along the path P1 and the slot cutting assembly 53 cuts the slots 28 in the fifth plank 90e that extend widthwise inwardly toward the factory edge 84. In order to advance the formed shake panel 20e, the rollers 58 are stopped and then the shake panel 20e is moved in an opposite direction along the path P2. Then, the slot cutting assembly 35b is pivoted to its retracted position.
The process of forming the slots 28 in the last plank 90e using the second cutting station 35b reduces the speed at which shake panels 20a-20e may be cut from the sheet 80 because the shake panel 20e is stopped and then moved in reverse in the direction along the path P2 in order to retract the cutting assembly 53. Additionally, the shake sections 30a of the last shake panel 20e cannot be trimmed using the fourth cutting station 35d due to the orientation of the shake sections relative to the blade assemblies 65 and 75 thereof. Furthermore, if each of the shake sections have a uniform length, the operator manually rotates the last shake panel 20e in order to stack it with the slots 28 oriented in the same direction of the shake panels 20a-20d. If the shake sections have different lengths (LS1, and LS2), the operator stacks the shake panels 20a-20d in one pile and stacks the shake panels 20e having shake sections 30 of uniform length in another pile.
Accordingly, there is still a need in the art for a more efficient cutting machine and method suitable for forming shake panels in which the bottom edge of the shake sections have a rough, cut surface finish. It would also be desirable that in such a cutting machine and method that the operator does not have to laboriously manually rotate the shake panels in order to stack them all in the same orientation. Moreover, it would be desirable that the cutting machine and method can cut shake panels, from a given a sheet, that all have the same shake section configuration.